Australia wants to show the world it is serious about space and is using years of well-honed hypersonic know-how to prove it by developing technology for a scramjet-based system for access to space.
The Scramspace 1 (Scramjet-based Access-to-Space Systems) project is the first step on the road to what the country’s nascent space business projects could be an affordable, reliable and repeatable launch system based on combined air breathing and rocket propulsion. Aimed at free-flight tests of a Mach 8 scramjet, Scramspace 1 has “passed its preliminary concept development phase, and is on track for launch in October 2012,” says Russell Boyce, project director and scientific lead.
Preliminary design review is set for July, with critical design review (CDR) in October says Boyce who is Defence Science and Technology Organization chair of hypersonics at the University of Queensland (UQ). The 1.84m (6-ft) long vehicle will be boosted by an S30 first stage and Improved Orion second stage to an apogee of around 340 km. Once clear of the atmosphere the nose cone will be ejected to expose the scramjet engine inlet.
Accelerating to Mach 8 on its ballistic descent, the bullet-shaped vehicle will re-enter at 100 km, deploy six stabilizing pop-out fins and at 35 km close bypass doors inside the vehicle to duct air through the primary flow path. The hydrogen-fueled engine will start and the primary experiment, lasting 2.5 sec, will take place as the vehicle hurtles down between 32km and 27km. Secondary and tertiary experiments, including a diode laser to sense oxygen levels in the axisymmetric inlet and advanced high temperature carbon-carbon materials with embedded sensors, are also planned.
Nico Reuther/Sandy Tirtey
“This is definitely not a cruise or thrust-producing vehicle, it is a scientific experiment,” says Boyce who adds the ground test element of Scramspace will “push the limits of scramjet operation to Mach 10, 12, 14 and maybe beyond. But just as importantly it pulls together the whole of Australia’s hypersonic community for a single program, and will help build a team of flight scientists and engineers for future programs.”
The major aim, however, remains focused on using Scramspace as a flagship program to strengthen Australia’s credibility in the international space community, building on the policy goals set by the recently established government Australian Space Research Program (ASRP). Set up to foster the space industry by encouraging collaboration between small groups and centers to achieve critical mass, the ASRP is partially funding the A$14 million Scramspace effort.
Led by UQ, Scramspace partners include academia, industry and international government research agencies. Australia’s other key academic hypersonic research players in the project include the Universities of New South Wales, Adelaide and Southern Queensland, while government and industry members include DSTO; BAE Systems, AIMTEK and Teakle Composites. International partners include the German Aerospace Center and Italian Aerospace Research Center, both supporting the materials testing with ceramics, as well as the Japanese Aerospace Exploration Agency (supporting optics for the laser experiment), and the University of Minnesota; as well as involvement from the Australian Youth Aerospace Association.
Ground tests and engineering work continue in the run up to CDR with recent work including demonstration of the inlet door flow characteristics at the UQ wind tunnel facility in Queensland. “We’re working on shrinking the diode laser this year,” adds Boyce who says the time is ripe to capitalize on Australia’s hypersonic heritage gained through test efforts with the U.S. such as HyCAUSE and HySHOT, and continuing today with HIFire. The Australian government is “developing an enduring space policy, and fortunately for us, hypersonics is considered to be a key part of that – and it is gathering momentum,” he says.